This invention generally relates to haircut scissors. More particularly, this invention relates to haircut scissors that prevent hairs from escaping along the haircut edges of the haircut scissors so as to achieve neat and efficient haircut.
It is known that hairs pinched between haircut edges 102 of a conventional pair of haircut scissors 101 escape or slip as indicated by an arrow in the accompanying FIG. 5, and often partially remain uncut. Hairs which are neatly combed tend to be cut along a curved line with a conventional pair of haircut scissors against intent as shown in the accompanying FIG. 6 due to slippage of the hairs along the haircut edges of the scissors.
Such slippage of hairs can take place with conventional thinning scissors or shears as well. In an attempt to prevent such slippage, a conventional pair of thinning scissors are provided with V-shaped or U-shaped haircut edges 202 between protrusions as shown in the accompanying FIG. 7. Hair slippage on the haircut edges 202 of the thinning scissors is thus effectively prevented.
The assignee of this application disclosed in International Application No. PCT/JP99/05381 slits 304 having a predetermined length and width as schematically shown in the accompanying FIGS. 8, 9 and 10 which are provided at intervals along a haircut edge L of a pair of haircut scissors. The width W of these slits 304 is smaller than twice that of a typical hair. These slits 304 provide the following advantageous features.
Even when the width W of the slits 304 is somewhat smaller than that of a typical hair, a hair X which is sliding on the haircut edge L in the direction indicated by an arrow will itself get caught on the mouth 305 of one of the slits 304 and obstruct movement of other hairs that follow as shown in the accompanying FIG. 8. Thus, slits 304 having a width W which is smaller than that of a typical hair will work as a hair slippage stop.
When the width W of the slits 304 is as large as that of a typical hair, a hair or hairs X traveling in the direction indicated by an arrow will somehow get into one of the slits 304 and obstruct movement of other hairs that follow as shown in the accompanying FIG. 9. Thus the slits 304 having a width W as large as that of a typical hair will work as a hair slippage stop.
When the width W of the slits 304 is nearly twice that of a typical hair, a plurality of hairs will enter slits 304 one after another or get caught together at the mouth 305 of slits 304 as shown in the accompanying FIG. 10. Thus the slits 304 which possess a width which is greater than that of a typical hair but smaller than twice that of a typical hair will also work as a hair slippage stop.
Slits 304 provided at intervals along a haircut edge L of a pair of haircut scissors, whose breadth W is made smaller than twice that of a typical hair, can effectively prevent hair slippage.
When cut, hairs whose breadth W is smaller than that of the slits 304 may get temporarily stuck within the slits 304, however, they will eventually and naturally fall out of the slits during use of the haircut scissors. Hairs whose width W is larger than that of the slits 304 may also be squeezed somehow into the slits 304 and remain within the slits. However, the stuck hairs can be raked out easily with fingers or readily brushed off.
Some people, however, particularly love cleanliness. Such people hate to see any cut hairs remain within the slits 304 even temporarily. Downy hairs will get caught within the slits 304 more easily than full fledged ones. Professional barbers as well as beauticians therefore cannot disregard as trifles such particularity of their customers.
In addition, thick hairs will be damaged if they are forcedly pressed into narrow slits 304 or scraped against the side edges of the slits 304. Such damage should be carefully avoided.
Accordingly, it is an object of the present invention to provide a pair of haircut scissors having such slits that can effectively eliminate hair slippage on a haircut edge or edges of the haircut scissors without damages to hairs.
It is another object of the present invention to provide a pair of haircut scissors having such slits that can prevent cut hairs from getting stuck within the slits.
According to an embodiment of the present invention, as defined in the attached claim 1, fine slits are arranged along a haircut edge of a pair of haircut scissors. Each slit is provided thinner than twice the thickness of a typical hair, and is filled up with a filler. One reason why the slit should be thinner than twice the thickness of a typical hair is that if the slit is more than twice as thick as a typical hair, the haircutting performance of a pair of scissors incorporating such slits will become poor. A top portion of each filler is chipped off to a degree to provide a microscopic nick so as to catch a hair or hairs therewith, effectively preventing hair slippage or escape on the haircut edge.
It is to be noted that the term xe2x80x9ca pair of scissorsxe2x80x9d as used herein includes a pair of thinning scissors or shears and other scissors used to cut hair.
The filler will not hinder the expected function of the slit because the nick compensates that expected function. There are a number of ways to provide such a filler having a nick.
The nick of a filler may be provided concurrently with whetting processes of the haircut edge, as defined in the attached claim 2, since amicroscopic top portion of the filler is very thin and thus relatively or very fragile. The nick may be so small as to be virtually indiscernible to the naked eye.
The haircut edge of a scissors blade requires whetting once in a while in order to retain professional cutting property. Each whetting process will produce a fresh nick on the filler. Therefore, the filler will always have a nick at its top edge.
The filler may be provided so flexible as defined in the attached claim 3 as to be pressed and deformed by a hair or hairs to provide a nick. Such a flexible filler may be an elastically deformable material such as a rubber material, or a plastically deformable material such as a plastic material or a soft metallic material.
A plastically deformable filler will provide a permanently deformed nick when its top edge is pressed by a hair, while an elastically deformable filler will provide a temporarily deformed nick which will disappear when the pressure from a hair is removed. These fillers eliminate nick forming processes.
A filler of the present invention may be provided by plating means as defined in the attached claim 4. A metallic material when plated in the fine slit will fill up the void of the slit. The filler when formed in the slit by plating means will provide a natural notch in an indeterminate form at a top edge portion of the filler as will be readily appreciated by a person skilled in the art. The plated filler is stable and rigid.
The attached claim 5 defines use of metallic powder whose melting point is somewhat lower than the metallic material of a scissors blade where slits are formed. The powder is filled up in each slit and immersion plated with the same or different metallic material whose melting point is the same or only slightly different from the powder material to form a filler in the slit. The metallic powder may be Au, In or Sn, and the immersion plating material may also be Au, In or Sn, or other materials whose melting points are respectively close to those of the powder materials.
A method for providing a pair of haircut scissors which include a scissors blade having a plurality of slits each with a filler which is formed by plating is defined in the attached claim 6.
The filler may be provided by electroplating as defined in the attached claim 7. Electroplating will fill up the void of each slit with a plating material. An adequately formed filler may be provided in the slit by repeating the plating process, if a single process has proved to be inadequate. The scissors blade may be masked except in the slits to provide improved and stable plating of fillers in the slits.
Such plating may be provided with an Au material for example, and the masking may be provided with a resist plating ink, masking paint, chromium oxide plating material or enamel paint. Other plating and masking materials may equally be utilized.
Such plating may be provided by immersion plating with a metallic material having a lower melting point than the metallic material of the scissors blade as defined in the attached claim 8. Immersion plating may be advantageously utilized for xe2x80x9cthickxe2x80x9d slits where electroplating alone may be insufficient.
The attached claim 9 defines plating in the slits on a ferrous scissors blade. Although scissors materials are generally ferrous materials such as stainless steel materials, nonferrous materials as well as hard metals or alloys may be used as well. Therefore, the method for plating as well as the plating material should be appropriately selected taking the scissors blade material used into consideration.
A scissors blade made of a ferrous material is subjected to slit-filler processes. The ferrous scissors blade, after or before its final forming processes, is masked with a plating resist and then provided with numerous slits on the haircut edge of the scissors blade. The masking material may be a nonconductive resin, chromium oxide or Sn/Ni material. Other appropriate masking materials may also be adequately utilized.
The slits are exposed without a masking resist film. The slits are then activated, e.g. by anodic electrolysis in phosphoric acid, and immersion plating in hydrochloric acid or phosphoric acid. The activated slits are electroplated in a plating bath, and a bonding film is formed on the slit walls. The plating bath material for electroplating may be Ni, Au, Cu, Fe, Sn/Pb, Sn/Ag or Sn/Bi. Other plating materials may also be equally utilized.
The slits having a bonding film on the inner surfaces thereof for improved wettability are further immersion plated with a plating material having a lower melting point than the material of the scissors blade so as to provide fillers of the present invention in the slits. The plating material having a lower melting point than the scissors blade may be Sn/Ag alloys, Sn/Ag/Cu alloys, Au materials, In solder materials or In alloys. A chief reason the immersion plating material should have a lower melting point than the material of the scissors blade is to avoid tempering of the scissors blade. If not, the haircut edge will get dull.
An alternative method is provided as defined in the attached claim 10, where slits are prepared on the haircut edge of a scissors blade before its masking process unlike the foregoing method according to the attached claim 9. Masking with a plating resist is provided on the scissors blade except the slits, e.g. by printing means. The side walls of the slits are thus exposed, which are activated and electroplated as taught in relation to the attached claim 9. A bonding film is provided on the side walls of the slits.
The scissors blade with the slits is immersion plated in an immersion plating bath of a metallic material which has a lower melting point than the material of the scissors blade. The fused immersion material forms fillers on the bonding film in the slits.
This method provides an advantageous feature over the method of the attached claim 9. According to the method of the claim 9, slits are provided on the cutting edge of a scissors blade after a masking process. Slits of the present invention may advantageously be provided with a rotary disk grinder. When the masking material is a paint type, the paint may stick onto the disk grinder to the detriment of the function of the disk grinder. When the masking material and the disk grinder are not congenial with each other, the disk grinder may not provide efficient and precision cutting, or may be broken or damaged otherwise. The method according to the attached claim 10 solves such problems.
The masking material may accidentally enter the slits, which hinders steady formation of a bonding film and thus hinders formation of fillers in the slits. In order to prevent the masking material from accidentally entering the slits, the attached claim 11 provides another alternative method.
This method applies on a scissors blade made of a ferrous material. First, slits are provided on the haircut edge of the scissors blade. The scissors blade is wholly activated or selectively and partially activated including at least the slit portions as previously described. The scissors blade is then electroplated without masking so that a bonding film is formed on the activated surfaces of the scissors blade including the slits.
Next, the slits are masked with a plating resist, and the other portions of the scissors blade are made nonconductive by applying thereon, e.g. lithium silicate (water glass), nitric acid, electroplating paint or chromium oxide so that the nonconductive surfaces shed a molten immersion plating material during a subsequent immersion plating process. After this non-conductivity treatment, the masked material of the slits is removed and a metallic material having a lower melting point than the metallic material of the scissors blade is immersion plated so that fillers are formed on the bonding film in the slits.
The electroplating for forming a bonding film in the slits may be performed using an Ni material or Fe material, then using an Au material, as defined in the attached claim 12. The fillers provided on the bonding film in the slits are stable.
The thickness of the Ni or Fe film is preferred to be between 0.5 xcexcm-1.5 xcexcm. If the thickness of the bonding film is below 0.5 xcexcm, the filler formed thereon will not be stable, and if the thickness exceeds 1.5 xcexcm, the bonding film will be undulated and microscopic voids will be generated in the bonding film. As for the Au film, the thickness is preferred to be between 0.05 xcexcm-0.2 xcexcm.
The method defined in the attached claim 13 uses metallic powder to form cores of the fillers in the slits. A metallic material having nearly the same melting point as the powder is used to immersion plate the scissors blade whose slits are packed with the metallic powder. Formation of microscopic voids or bubbles in the fillers can be effectively avoided.
An appropriate metallic powder material may be soaked in a flux, which facilitates easy packing of the powder in the slits. A preferred average particle size of the metallic powder is 20 xcexcm. Other sizes may be equally utilized.